Emotion-related processes play an important role in the development of aggression and antisocial behavior. What is not known is the extent to which these emotion-related processes or their relationship to antisocial behavior may be genetically or environmentally based. We propose to investigate the genetic and environmental bases of psychophysiological and behavior indicators of emotion processing and responding, and their relationships to aggression and antisocial behavior in an ongoing study oft-wins (age 9-10 years). As part of this NIMH-funded investigation (Risk Factors for Antisocial Behavior; MH 58354), we have implemented a psychophysiological and behavioral assessment protocol for understanding emotion-related variables in the development of antisocial behavior and aggression. These involve teacher ratings of children's emotion regulation and outcomes (emotionality and lability), as well as a comprehensive psychophysiological assessment of emotional processing and responding: autonomic nervous system (ANS) measures (both electrodermal and cardiovascular recordings, including vagal tone), electrocortical (EEG and ERP) measures, and electromyographic (ECG) measures of startle potentiation. Additional tasks have been included in the psychophysiological protocol in order to measure emotional processing (fear and sadness) during film clips, startle modulation to emotionally laden stimuli (faces), anticipatory fear (using a countdown procedure), and responses to embarrassing questions. We have also added two tasks that tap less voluntary attentionat processes-auditory sensory gating (during a P50 gating task), and auditory sensory discrimination (during a mismatch negativity task). [unreadable] [unreadable] With this comprehensive assessment we are in a position to investigate the genetic and environmental basis of emotional-related processes and their relationships to antisocial behavior in children on the brink of adolescence. These variables will continue to be of considerable significance during planned follow-up assessments, enabling differentiation among several antisocial pathways, including those leading to violence and substance use. Supplemental funding is requested to continue with data collection, processing, and analysis of this expanded assessment of emotion-related processes and outcomes. These new data will provide a tremendous opportunity to investigate the genetic and environmental bases of emotional responding and its relationship to antisocial behavior. These findings will provide a better understanding of the roots of human aggression, which may ultimately lead to more effective avenues for treatment and prevention of this important social problem. [unreadable] [unreadable]